In spectacle frames, frame components, and frame components and lenses, are usually attached to each other by screws. This requires great accuracy in the locating and drilling of the holes. It also increases the number of components, and can make life difficult for optical technicians when assembling frames, inserting or removing lenses, or repairing frames. For attaching a frame component to the lens, particularly for rimless frames, or partially rimless frames, if there is an error, or adjustment is required, a new lens may have to be made. This is time consuming for the technician and relatively expensive to the consumer.
Also, spectacle frames assembled without screws or use of soldering, have been made with a front, and two temples, all being made from moulded acrylic or plastic releasably secured together using a complex arrangement requiring special tools. This is inconvenient for opticians, who would find it much easier if they could insert lenses into, and remove temples from fronts without requiring special tools. Furthermore, to provide spring functionality in the temples normally requires a separate spring.